The start of NFL training camps is inching closer, but there's still some work to be done.

On Monday, the Titans take the field for another round of organized team activities. There's a three-day minicamp scheduled for next week. Training camp begins late next month.

With more than half of the OTA sessions complete, here are five Titans who have stood out:

QB Marcus Mariota. The first-round pick is drawing all the attention, of course. He has looked better than I thought he would out of the gate, with impressive arm strength and confidence running the offense. He's bound to have some disastrous days as he finds his way, but he's not yet come close to embarrassing himself.

CB Perrish Cox. The former 49er has been one of the defense's most consistent performers. I thought he'd bring a brash, more physical style of play to his side of the field; now I feel that way even more. Coaches seem hesitant to declare Cox the starter opposite Jason McCourty, but it will be a surprise if he's not.

ILB Zach Brown. He won over a skeptical coaching staff last offseason, earned a place in the starting lineup — and then suffered a season-ending injury on the fourth play of the opener. With the speed and playmaking abilities he's displayed so far this summer, I'll be surprised if he's not a Week 1 starter.

RB Bishop Sankey. I'm not saying he's ready for a breakout year after an underwhelming rookie season. But I have been impressed with his work in non-contact drills. When you consider he was absent last offseason because of school commitments, this has to be viewed as a positive.

OLB J.R. Tavai. The undrafted free agent from USC has been running with the first-team defense opposite Derrick Morgan, and that has to be considered a surprise. Some factors have contributed to the longer look — Brian Orakpo and Jonathan Massaquoi have been held out of team work while recovering from surgeries — but Tavai has played well and coaches are praising him. Now he must prove he can make plays in space as well as turn and run in coverage.